A proposal by Tracie Perez, a graduate student in the Mechanical and Aerospace Engineering Department, has been accepted by Google for one its “Summer of Code” projects.

The project, entitled “Implementation of LDPC encoder and decoder in GNU Radio,” focuses on satellite radio communication.

According to Perez’s advisor, Ben Harris, the Summer of Code is an initiative by Google to involve students with open source programming. It is a yearly event in which students from all over the world are supported by Google to complete a project that is proposed by the student. “Its name is derived from the (in)famous summer of love of 1967, hinting at the vision the open source community has for software, something that should be an open community asset,” Harris explained.

Google's award process matches mentors to mentees. Open source projects submit ideas for student projects to Google. Then Google evaluates the ideas and the capability of each project to mentor students. “My mentor is an experienced GNU Radio developer at KIT in Germany, and I’m also collaborating with another student at the Indian Institute of Technology. Having a personal mentor throughout the summer will ensure that my contribution is a success, and I'm sure that I will become a much better programmer after being under his guidance for a few months. Besides my mentor, there are many other world-class digital signal processing developers that are a part of the GNU Radio Community. I will be able to learn from them, and also once the summer is over, I'll have established a relationship with the community,” Perez explained.

She will use the C++ and Python languages to create new code for the GNU Radio project, which is a free and open-source toolkit used for implementing software-defined radios. “Because we need to communicate with satellites via radio, using a software-defined radio allows for rapid configuration changes and testing,” she explained. “I suspect that the code that I write and contribute over the summer will be directly used during my research. Even better is that it will also be available for everyone in the GNU Radio community through an open source license.”

Each open source project in the Summer of Code is allocated a number of “slots,” each of which represents a student project. Students around the world review the ideas listed by the open source projects and come up with their own work proposals. Only a fraction of proposals are accepted. This year, only 1,192 proposals were accepted of 5,999 received. Each student receives a stipend of $5000 for work done as part of the project.

“I am very proud that Tracie got this award. This is her first research proposal. Her competition was tough, but her experience working at NASA with operations of the International Space Station, and with GPS R&D, helped,” said Harris.

Perez is a graduate researcher in Harris’s Satellite Technology Lab (STL). The STL is working to solve a problem associated with making the next generation in satellites, called femtosatellites, that have a mass less than 100 grams. For these tiny satellites, getting a radio signal is a major challenge. In low Earth orbit (LEO), they are limited to 5 milliwatts of power, so the signal cannot be wasted on error checking. Perez has proposed a way to approach the theoretical maximum of the amount of information you can get from the signal, while retaining the ability for error checking.

“I think this project will be important to our research in the Satellite Technology Lab because we are about to establish an antenna farm on the roof, and we will hopefully soon be tracking satellites. Having development experience with GNU Radio will allow me to implement software radio tracking designs for our lab,” said Perez.